Potential role of short-chain fatty acids in the development of extraintestinal manifestations of Crohn’s disease

The metabolomic profile, particularly short-chain fatty acids (SCFAs), in Crohn’s disease (CD) and ulcerative colitis (UC) is an actively explored research area. Considering their immunomodulatory properties, SCFAs may contribute to the development of extraintestinal manifestations (EIMs). Objective. To compare SCFA levels in patients with CD and UC based on the presence of EIMs and to describe the structure of EIMs in the cohort. Material and methods. This prospective cohort study included 80 patients with inflammatory bowel disease (47 with CD and 33 with UC). Clinical and diagnostic evaluations were conducted at Stage I. At Stage II, stool samples from 60 patients meeting inclusion criteria were analyzed for SCFAs using gas-liquid chromatography. The following were measured: C2 (acetic), C3 (propionic), C4 (butyric), total C4 isomers, C5 (valeric), and C6 (caproic). Calculated parameters included total SCFAs (C2—C6) and the anaerobic index. Results. EIMs were observed in 53.2% of CD patients and 51.5% of UC patients; clinically active EIMs were found in 34.0% and 42.4%, respectively. Among CD patients, significant differences in SCFAs were found: mean C4 levels were lower in those with EIMs (0.62 vs. 1.41, p=0.008), as was total C2—C6 content (4.04 vs. 6.67, p=0.019). No significant differences were observed among UC patients. Conclusion. Total SCFA concentration (C2—C6) and butyric acid (C4) may serve as potential diagnostic markers for EIMs in patients with CD.